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124 HUNTER ON THE TEETH.

The first five may be called the permanent Teeth : they differ
from the temporary in having larger fangs. The permanent
Incisores and Cusjiidati are much thicker and broader, and the
Molarcs are succeeded by Bicuspidcs, which are smaller, and
have but one fang.
All these permanent or succeeding Teeth are formed in dis-
tinct Alveoli of their own ; so that they do not fill up the old
sockets of the temporary Teeth, but have their new Alveoli
formed as the old ones decay.

twenty anterior permanent teeth are developed in the fifth month of foetal
life. Robin and Magitot say they originate some before and some after
birth. According to Goodsir, the papilla of the second molar appears about
the seventh month after birth, that of the third about the sixth year.
Calcification begins first in the anterior molar. The process is a
little earlier in the teeth of the lower jaw than in the upper. The fol-
lowing is the order in which the process of calcification has been ob-
served to take place in the permanent teeth of the upper jaw. First
molar, five or six months ; central incisor soon after ; lateral incisor and
canine, eight or nine months ; two bicuspids, two years and over
;
second molar five or six years third molar, or wisdom tooth, about
;
twelve years.(l) Mr. Tomes gives the following description of the condi-
tion of the permanent teeth at the period when all the temporary teeth
are perfected, but the first true molars have not cut the gums :— " The
crowns of the permanent incisors, both of the upper and lower jaws, are
perfected, excepting perhaps at that part where the enamel terminates.
There the dull and chalk-like appearance, which that tissue presents
when the development is progressing may be observed. The canines are
still less advanced, while the crowns of the first bicuspids have not
attained to more than two-thirds, and those of the second bicuspid not
more than a third, of their ultimate lengths. The crowns of the first
permanent molars are, as respects their external surface, fully developed
;
and the septa of dentine which extend across the base of the pulps mark-
ing out the several roots yet to be developed are fully pronounced. The
second permanent molars are at present represented by about two-thirds
of their crowns, and invested with a thin layer of partially-developed
enamel. The positions of the pulps of the wisdom teeth are but faintly
indicated by slight depressions in the bone posterior to the sockets,
which contain the forming second molars. These marks may, however,
at this period, be altogether wanting.(2)]
(1) Quain and Sharpey, op. tit.
(2) Tomes' System of Dental S Surgi n . p. 60.